The fish landings were estimated to be worth more than £47m. The company was accused of being involved in a web of deceit motivated by greed.

At the High Court in Edinburgh, Shetland Catch, based in Lerwick, was also fined £150,000.

Solicitor General Lesley Thomson QC said: "Shetland Catch Ltd sought to make huge financial gain with total disregard for the law.

"They knowingly assisted vessel skippers to under declare their fish landings and were involved in a web of deceit with their sole motivation being greed."

Det Supt Gordon Gibson, of Grampian Police, said he hoped the confiscation order would send a "very clear and lasting message that this will not be tolerated by the courts and society in general."

Marine Scotland said there had been an unprecedented scale of illegal activity and deception involved.

Head of compliance Cephas Ralph said: "Shetland Catch Ltd developed sophisticated techniques with the sole purpose of concealing the true level of landings from our officers; therefore it is right that those involved face the consequences of their actions."